Rotary pump with sliding plates



E. HENRY.

ROTARY PUMP WITH SLIDLNG PLATES.

APPLICATION FILED MAY 10, |920.

mente@ July 26, 1921.

Q infn. N n N a Sveva .n EN .s

-ENR T PATENT OFFICE.-

EDLIOND HENRY, F PARIS, FRANCE.

ROTARY PUMP WITH Specication of Letters Patent.

SLIDING PLATES.

Patented July 2e, 1921.

Application med lay 10, 1920. Serial No. 380,881.

' To all wlwm t may concern.'

Be it known that I, EDMoND HENRY, residing at 19 Rue du Poteau,at Paris, Department of the Seine, France, have invented certain new and useful Improvements in Rotary Pum s with Sliding Plates, for which I have led application in France May 3, 1919, and of which the following is a specication. I

This invention relates'to improvements 1n rotary pumps with sliding plates, for the purpose of reducing the internal friction and resistance effects and of thereby increasing fthe mechanical efficiency, at the same time affording a simplified construction 'which provides for an easy dismounting and assembling of the parts. These improvements are applicable to l ,fliffluid pumps as well as to pumps employed for -the compression of gases orfor producing a vacuum, and also to hydraulic motors containing any number of sliding plates.

The sald improvements consist chieily on theone hand, in the method employed to regulate the movement of the sliding plates out of the grooves in the piston in which they are contained as well as the return movement of the plates into the said grooves, by means of two parallel ring-shaped membersl disposed one on each side of the rotating piston and adapted to rotate freely by means of one of their edges which engages a bored out portion in the end of the mam body of the pump concentric to the axis of the latter, the said ring-shaped members having their other edge engaging the sliding plates by means of suitable cut out portions in the latter and if necessary through the medium of elastic means; and on the other hand in the method of mounting the piston on its shaft in such manner as to provide for a slight longitudinal displacement of this latter under the action of lateral pressures, means being provided for properly limiting thel sliding movement of the shaft. It is understood that the hereinbefore mentioned arrangements can be employed in combination or independently, and all of these concur in the same end, viz, to diminish the internal friction effects and resistances which are injurious to the mechanical efciency, this result being obtained while at the same time providing as set forth hereunder a construction of a simple character and providing for an easy dismounting and assembling on the spot.

In the presentdescription, the invention 1s supposed to be applied to a pump-having a piston mounted eccentrically with reference to the main body of the pump.

In the accompanying drawing which is given by way of example, Figure 1 represents a dpump of this kind in vertical section perpen icular to its axis, Fig. 2 vis a vertical section along the axis. Figs. 3 and 4 are partlal sections taken respectively perpendlcular to and along the said `axis and showing the method of disposing the elastic means between the ring-shaped members and the sliding plates.

The cylindrical body of the pump, a, which is closed by two covers b, b forming end cover plates, contains the movable iston c which is also of cylindrical form but is mounted in eccentric position with reference to the main body a in such manner that it shallbe tangent at its lowest point to the interlor surface of the said main body of the pump.

This tangency may take place according to a generatrix of the cylinder, or as represented in the drawing according to a surface of contact. In the latter case, of the surface of Contact which belongs to the pump body is not centered according to the axis of the latter, but with reference to the axis of the piston, and the middle part of this surface portion is formed by an independent member "d which is movable in a groove in the cylinder and is driven constantly against the piston' by means of a flat spring e in such manner that in spite of the wear of the parts, a good contact shall be always maintained and with a minimum amount of friction.

The sliding plates f1, f2, 3, f4 are disposed in the usual manner to slide by easy friction within corresponding radial grooves in the piston. On each side of the latter is disposed perpendicular to the shaft y' a ringshaped member g or g', guided by means of its outer edge which moves within a circular recess z or z" bored in the corresponding end plate b or b of the pump body and concentric with the axis of this body, while its inner edge enters into suitable out out ortions k1 or k2 of the sliding blades. he said ring-shaped members can move freely in the recesses of the end plate and in the cut out portions of the sliding plates, but they are drawn along by the sliding plates during the rotation the portion of the piston while remainA-n nevertheless always concentric to the mam body of the pump during their movement.

In order to provide for the entraining of the said members with certainty, there are provided upon the rin shaped members on either side of the sli ing plates or on either side of two op ositely situated sliding plates the studs Z- adapted toreceive thev thrust of the corresponding sliding plate in case the entraining action has not taken lace and consequently to give rise to this atter movement. l

The part plyed by these ring-shaped members is re ily understood: under the action of centrifugal force, the sliding plates tend to bear upon the walls of the cylinder, and if they were free to move they would be projected against these walls, thus causing a frictional effect which increases with the speed, and.I this will cause a considerable in'- crease in the mechanical resistance. rlhe ring-shaped members act to prevent this effect b limiting the outward movement of the sliding plates to exactly the proper quantity in orderfthat the plates shall run ush with the walls and provide the required ti htness; by reason of their eccentric position with reference to the piston and their concentric position relative to the cylinder, the ring-shaped members cause the sliding plates to enter into their grooves as soon as they arrive in the inoperative position during*I the revolution.

Moreover, since a partial vacuum is produced on the side of the intake, while a pressure exists on the delivery side, the sliding plates are thus subjected .to efforts of a contrary nature, and on the intake side these would tend to force the plate out of the iston, while on the delivery side they wou d tend to force the plate back into the piston, if the ring-shaped members did not maintain the plates in their respective positions.

The said. rin -shaped members also have a veritable equllibrating action which still further tends to reduce the effect of centrifngel force, for in fact the mass of each p ate has opposed to it, as concerns centrifugal force, the mass of the assemblage formed by the other plates and the ringshaped members connecting all the' plates to ther.

n the pumps which operate at ,ve high speeds, the elements can be designe so as to keep the plates somewhat within their grooves in-order to prevent them from coming in contact with the walls of the cylinder, and this acts to suppress all friction.

For the lates which are employed to make a wor img joint, this very small setback of the plates will not prevent tightness, since thls is assured by the extremely high speed of the fluid,v in the parts of the pumpin which the sliding plates are inoperative, this setback is of no importance.

The operation remains quite the same as for all pumps of this class. The intake is effected through the neck m, for instance, and withthe piston rotating in the countter-clockwise direction, if the piston is' considered in the position indicated in Fig. 1, the plate f1 is engaged upon intake, and this will prevail until the plate reaches the edge n in the pump body; during this time the plate f2 is engaged upon delivery in the direction of the neck m', while the other two plates are inoperative during this period.

It is understood that a certain amount of playv is allowed where the ring-shaped members engage the cut out portions of the plates in order to provide for the displacement required by the fact that the angle between the plates and the ring-shaped members varies at each instant.

On the other hand it is advisable to provide proper arrangements whereby the plates are allowed a certain amount of radial displacement in order that they may move toward the center of the cylinder, especially in cases where the pumps are employed for the intake and delivery of liqnids which are subject to contain foreign bodies of a hard nature, for the purpose of avoidin any damage due to the latter. To this en the cut out portions of the plates are enlarged and in each ortion is disposed a flat spring, o or o', and the corresponding ring-shaped member. This spring bears simply by its free ends upon the periphery of the ring-shaped member and 1s slidable upon the latter, being fixed at its middle part upon one side of the cut out portion, as represented in Figs. 3 and 4.

The connection between the piston c and its shaft j Eis carried out by means of the long keys p, p which provide for a longitudinal sliding movement of this shaft, this being limited on each side by the washers g, q which are drawn along by the said keys during .the rotation of the piston, the keys striking against these washers. In this manner an interior lateral pressures exerted upon t e piston can be balanced, and should the shaft undergo a pressure upon one end, this pressure is not transmitted to the iston but is supported by the cylinder hea s through the medium of the said thrust washers, thus suppressing the increase in resistance which would be caused by the friction of the piston on the cylinder heads or end plates, and reducing the wear of the entire apparatus.

It is evident that the preceding arrangements will have the advantage of suppressing the friction effects which are injurious to mechanical efficiency and will provide a slmple construction and atleast a construcetween.l the plate body tion of a more simple nature than all others which have been hitherto employed for the same purpose. It is clearly shown in the drawings that it is a Very easy matter to dismount and to assemble the pump without being required to move the same. It suiices to remove one of the cylinder heads, whereupon the piston with its plates and ring-shaped members can be withdrawn; for the assembling, these latter members will fall in to place almost without ellort." As indicated in Fig. 1, the sight holes 1*, 1" with tight plugs can be provided around the cylinder for the purpose of inspecting the pump without being obliged to remove the cylinder heads or end plates. These plugs can be provided with the necks s, s for priming the pump.

Claims:

1. A rotary pump with sliding plates comprising, in combination, a cylindrical pump body having intake and delivery passages, a rotary piston with slidin plates and mounted eccentrically with re erence to the cylinder, two ring-shaped members freely rotatable by their outer edges within bored out recesses in the end plates of the pump and concentric kto the cylinder, and having their inner edges engaging grooves provided in the sides of the sllding plates, which grooves are wider than the said edges and elastic means provided upon each sliding plate between the said plate and the said ring-shaped member in order to allow the plate to enter within its groove in the piston while passing over an accidental. obstacle on the walls of the cylinder.

2. A rotary pump with sliding plates comprising, in combination, a cylindrical pump body having intake and delivery passages, a rotary piston rotated by means of a shaft disposed eccentrically with reference to the cyllnder, the said piston being slidahle lon-r gitudinally with reference to the shaft between two lateral stop pieces, plates slidable radially in the piston, and two ring-shaped members freely rotatable by their outer edges within bored out recesses in the end plates of the cylinder and concentric to the said cylinder, and having their inner edges engaging lateral grooves in the said plates for the purpose of maintaining and guiding the latter.

3. In a device of the class described, the combination with a cylindrical body having an inlet and outlet opening, a rotary piston eccentrically mounted with respect to the body, slots in said piston, slidable plates arranged in the slots, said plates having their inner ends of less width than their outer ends, recesses in said inner ends, corresponding grooves in the walls of the body, rings limiting the movement of said blades movably mounted in said recesses and grooves, and spring means in said body for forming a contacting surface at all times with the periphery of the piston.

In testimony whereof, I have signed my name to this specification.

EDMOND HENRY. 

